Night time photochemistry

This morning the Zeppelin took off 20 minutes earlier than expected, again with the direction to the four lakes south of Jämijärvi, where the airship cruised until 9am. Data showed again a well distinct layering structure of the atmosphere. After the airship will have ridden out the thunderstorm, we will build in the photochemistry package and start flying at 11.pm tonight.

From dusk till dawn

The Zeppelin lifted off at 8 pm this evening to fly above four lakes south of Jämijärvi for 4 hours. After 6 hours of rest we will continue to fly with the SOA package. The flight will start early at 6:30 local time to observe changes in the residual layer from the previous day.

Engine replaced

The new engine has arrived in Jämijärvi, but windy conditions prevented its installation. However, yesterday night it was calm and the engine could be replaced. The next flight will be a night flight with the SOA package this evening.

Zeppelin Engine Failure

After four days of waiting for good flight conditions we were looking forward to fly again. However, during engine startup, the left engine failed. We had to remove our racks. The engine could not be repaired and has to be replaced. Therefore, the Zeppelin must remain fastened to the mast truck until the beginning of next week.

Zeppelin crew members inspecting the defective engine.

 

A platform is prepared to repair the engine.

Early bird flight

Today we had to get up early to prepare the instruments for departing at 5:00 am local time. The Zeppelin flew height profiles close to the airfield with the photochemistry layout. The airship passed the airfield to times at low altitude to sample air close to the ground. Since thunderstorms were predicted for the afternoon the scheduled night flight had to be canceled.

Sunday flight, engine trouble and tests

On Sunday, we started flying at 7:00 am. We wanted to do vertical profiles until at least 11:00 am, because the evolution of the mixing layer into our lowest flight altitude was expected at around 10:00 am. Unfortunately, we had problems with the control of the aft engine, so the Zeppelin had to come back after three hours.

The engine was fixed within two hours, but then the winds were becoming to gusty. We could have flown for additional two hours, but it did not make so much sense scientifically and technically it would have been risky flight.

Actually, in the quick look data we discovered a potential contamination from inside the cabin affecting the HONO and NOX measurements.

Therefore, we decided to repeat this flight on Monday, in the same way as planned for Sunday.

We also did some tests to understand / get rid of the contamination. The result: the windows in the cabin doors should be opened after start to vent the air ship and prevent cabin air to reach the sampling points of LOP, COD and NOX. (In Italy these windows were always open / the cabin was cooled by actively sucking air through ventilators mounted in the rear door window.)

The flight started at 07:00 am and the airship returned at 13:00h.
Results: nice height profiles of the evolving PBL and resolving the contamination issue.

After landing we built out the FFL and LOP rack to be ready for a CL5-SOA flight.
At 17:00h we decided to cancel the flight for Tuesday, strong gusts and strong winds in flight height are expected.

It looks like 5 - 6 days of good weather are coming in a row. The current preliminary plan is to fly CL5-SOA on Wednesday.

Details will be decided on tomorrows (chemical) weather forecast.
It looks that Thursday might be a good day for a nucleation event.

Collecting data - and nice impressions.

Flight over Jämi Forest

On Saturday, the Zeppelin will fly with the photochemistry package close to Jämi. The start will be at 10:30, when the fog has lifted.

No Flights till Saturday

Thursday was rainy and gusty with no chance to fly. We used the opportunity and had a small party in our hotel to celebrate our successful first week in Finland. Thursday was also a public holiday in Finland and a lot of people came to visit the Zeppelin. The next flights will be on Saturday, when the  the photochemistry package will be installed.